DTC Troubleshooting: U1260(CVT (TCM)) (2020 2021)

DTC U1260  : Lost Communication With Auxiliary Transmission Fluid Pump

NOTE: 

• Before you troubleshoot, review the General Troubleshooting Information .
• This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

DTC(CVT)

1. Determine possible failure area (PGM-FI system, others)

   -1. Turn the vehicle to the ON mode.

   -2. Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P0A94 Voltage Stabilizer Malfunction

   Is DTC P0A94 indicated?

   YES 

   Go to the troubleshooting for DTC P0A94 in the PGM-FI system .

   NO 

   Go to step 2.

2. Problem verification

   -1. Select the Electrical Oil Pump Activation in the Function Test Menu, and drive the auxiliary transmission fluid pump for at least 5 seconds with the HDS.

   -2. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U1260 Lost Communication With Auxiliary Transmission Fluid Pump

   Is DTC U1260 indicated?

   YES 

   The failure is duplicated. Go to step 3.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between the auxiliary transmission fluid pump and the TCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

3. Determine possible failure area (power circuit, others)

   -1. Clear the DTC with the HDS.

   -2. Turn the vehicle to the OFF (LOCK) mode.

   -3. Disconnect the following connector.

   Auxiliary transmission fluid pump 4P connector

   -4. Turn the vehicle to the ON mode.

   -5. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	Auxiliary transmission fluid pump 4P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 1:
   Test point 2	Auxiliary transmission fluid pump 4P connector (female terminals) No. 4:

   Courtesy of HONDA, U.S.A., INC.

   Is there battery voltage?

   YES 

   Go to step 4.

   NO 

   Go to step 10.

4. Determine possible failure area (EOPSTS line, others)

   -1. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	Auxiliary transmission fluid pump 4P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 2:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there battery voltage?

   YES 

   Go to step 5.

   NO 

   Go to step 8.

5. Open wire check (EOPSIG line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Jump the SCS line with the HDS, and wait more than 1 minute.

   NOTE:  This step must be done to protect the TCM from damage.

   -3. Disconnect the following connector.

   TCM 50P connector

   -4. Measure the resistance between test points 1 and 2.

   Test condition

   Vehicle OFF (LOCK) mode

   	Auxiliary transmission fluid pump 4P connector: disconnected
   	TCM 50P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 3:
   Test point 2	TCM 50P connector No. 40

   Courtesy of HONDA, U.S.A., INC.

   Is there 1.0 Ω or less?

   YES 

   The EOPSIG wire is not open. Go to step 6.

   NO 

   Repair an open in the EOPSIG wire between the auxiliary transmission fluid pump and the TCM.

6. Shorted wire check (EOPSIG line)

   -1. Measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Auxiliary transmission fluid pump 4P connector: disconnected
   	TCM 50P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 3:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there 1 MΩ or more?

   YES 

   Repair a short to ground in the EOPSIG wire between the auxiliary transmission fluid pump and the TCM.

   NO 

   The EOPSIG wire is OK. Go to step 7.

7. Auxiliary transmission fluid pump check

   -1. Reconnect all connectors.

   -2. Test the auxiliary transmission fluid pump .

   Is the auxiliary transmission fluid pump OK?

   YES 

   The auxiliary transmission fluid pump is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, replace the original TCM .

   NO 

   Replace the auxiliary transmission fluid pump .

8. Shorted wire check (EOPSTS line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Jump the SCS line with the HDS, and wait more than 1 minute.

   NOTE:  This step must be done to protect the TCM from damage.

   -3. Disconnect the following connector.

   TCM 50P connector

   -4. Measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Auxiliary transmission fluid pump 4P connector: disconnected
   	TCM 50P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 2:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there 1 MΩ or more?

   YES 

   The EOPSTS wire is not shorted. Go to step 9.

   NO 

   Repair a short to ground in the EOPSTS wire between the auxiliary transmission fluid pump and the TCM.

9. Open wire check (EOPSTS line)

   -1. Measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Auxiliary transmission fluid pump 4P connector: disconnected
   	TCM 50P connector: disconnected
   Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 2:
   Test point 2	TCM 50P connector No. 50

   Courtesy of HONDA, U.S.A., INC.

   Is there 1.0 Ω or less?

   YES 

   The EOPSTS wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, replace the original TCM .

   NO 

   Repair an open in the EOPSTS wire between the auxiliary transmission fluid pump and the TCM.

10. Open wire check (EOPGND line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Measure the resistance between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode
    	Auxiliary transmission fluid pump 4P connector: disconnected
    Test point 1	Auxiliary transmission fluid pump 4P connector (female terminals) No. 1:
    Test point 2	Body ground

    Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The EOPGND wire is OK. Go to step 11.

    NO 

    Repair an open in the EOPGND wire between the auxiliary transmission fluid pump and ground (G151), or repair poor ground (G151).

11. Fuse check

    -1. Check the following fuse.

    Fuse

    No. F3

    Is the fuse OK?

    YES 

    The fuse is OK. Reinstall the fuse, then go to step 12.

    NO 

    Replace the No. F3 (7.5A) fuse, and recheck. If the fuse blows again, repair a short to ground in the No. F3 (7.5A) fuse circuit.

12. Relay check

    -1. Remove the auxiliary transmission fluid pump relay .

    -2. Test the auxiliary transmission fluid pump relay .

    Is the relay OK?

    YES 

    The auxiliary transmission fluid pump relay is OK. Go to step 13.

    NO 

    Replace the auxiliary transmission fluid pump relay.

13. Open wire check (+B EOP line)

    -1. Turn the vehicle to the ON mode.

    -2. Measure the voltage between the following test points and body ground individually.

    Test condition	Vehicle ON mode
    	Auxiliary transmission fluid pump relay 4P socket: disconnected
    	Auxiliary transmission fluid pump 4P connector: disconnected

    Connector	Terminal
    Auxiliary transmission fluid pump relay 4P socket (female terminals):	No. 2
    	No. 4

    Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The +B EOP wire is OK. Go to step 14.

    NO 

    Repair an open in the +B EOP wire between the auxiliary transmission fluid pump relay and the DC-DC converter.

14. Open wire check (EOPRLY/EOP RLY CL- line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    NOTE:  This step must be done to protect the TCM from damage.

    -3. Disconnect the following connector.

    TCM 50P connector

    -4. Measure the resistance between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode
    	Auxiliary transmission fluid pump relay 4P socket: disconnected
    	Auxiliary transmission fluid pump 4P connector: disconnected
    	TCM 50P connector: disconnected
    Test point 1	Auxiliary transmission fluid pump relay 4P socket (female terminals) No. 3:
    Test point 2	TCM 50P connector No. 27

    Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The EOPRLY/EOP RLY CL- wire is OK. Go to step 15.

    NO 

    Repair an open in the EOPRLY/EOP RLY CL- wire between the auxiliary transmission fluid pump relay and TCM.

15. Open wire check (EOPVB/EOP RLY OUT line)

    -1. Measure the resistance between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode
    	Auxiliary transmission fluid pump relay 4P socket: disconnected
    	Auxiliary transmission fluid pump 4P connector: disconnected
    	TCM 50P connector: disconnected
    Test point 1	Auxiliary transmission fluid pump relay 4P socket (female terminals) No. 1:
    Test point 2	Auxiliary transmission fluid pump 4P connector (female terminals) No. 4:

    Courtesy of HONDA, U.S.A., INC.

    Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The EOPVB/EOP RLY OUT wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, replace the original TCM .

    NO 

    Repair an open in the EOPVB/EOP RLY OUT wire between the auxiliary transmission fluid pump relay and the auxiliary transmission fluid pump.